Commentary on the economic , geopolitical and simply fascinating things going on. Served occasionally with a side of snark.

Sunday, March 9, 2014

Fukushima nuclear disaster Weekly Updates - March 9 , 2014 .... Concurrent nuclear disaster ironically ongoing at WIPP in New Mexico , US and ongoing problems with Hanford nuclear facility ( Washington state ) reviewed ..... Anyone still convinced nuclear power is safe and ultra hazardous contamination can be contained for the decades / hundreds of years it must be contained to prevent wide ranging problems ?

Following up this article.. 1.9 mSv/h detected at 54 m above ground along the damaged stack[URL]

Tepco is going to install covers over the facilities to protect against the damaged stack. The stack is 120m tall and have the damages at 66m height from the ground. Even a bolt would cause a significant damage by falling to the neighboring facilities.

The coolant system of reactor1 spent fuel pool will be suspended for 11 days from 3/14/2014 due to the installation.

The stack has 8 damages and 5 parts are cut off, however Tepco cannot dismantle it. It is not known how to dismantle the stack either.

Related article.. [Damaged stack] Tepco “looking for” the way to dismantle / cover the stack for high level of radiation [URL 2]

Highly contaminated water found leaked from a desalination system again. Tepco employee found in the morning of 3/9/2014.

According to Tepco, the leaked volume was 1.25 L, it is retained inside of the local dam.

They measured 23,000,000,000 Bq/m3 of All β nuclides (Including Strontium-90) from the leaked water. This is nearly the same level as the water to be processed in this system. It is assumed that the contaminated water leaked before entering this purifying system.

Tepco sprinkles contaminated water in the plant area on a daily basis. NRA (Nuclear Regulation Authority) pointed this out on the working group meeting of 3/5/2014.

According to Tepco and NRA, the sprinkled water is the groundwater that flowed into the basement of reactor5 and 6. These two reactors are shut down but the groundwater pumping up system is still malfunctioning. Groundwater therefore automatically flows into the buildings.

Based on Tepco’s analysis, it contains 3,000,000 Bq/m3 of Tritium. For example, the sprinkled water volume on 2/25/2014 was 72m3. They also sprinkled 76m3 on 2/26/2014.

The sprinkled water is assumed to flow into the groundwater stream, and go to the sea in the end. However because it is not through the drains, Tepco states it’s not considered to be “discharge”.

Following up this article.. One of the last 2 thermometers in reactor2 RPV was broken / Tepco possibly destroyed it during the test [URL]

On 3/7/2014, Tepco admitted they burnt and cut one of the last two thermometers in reactor2 RPV by themselves.

Now there is only one thermometer left in the vessel. It is estimated to take 3 months to replace it with a new one.

It was due to another mis-operation. According to Tepco, they put 2.5 times high voltage as the limit to the thermometer on the insulation resistance.

They had the manual, but the operator didn’t notice the voltage limit.

Because of the high level of atmospheric dose in Fukushima plant, experienced workers are forced to leave. Having the increasing demand in workers for Olympic game construction and also the restart of other nuclear plants, it is concerned that Tepco is actually in the serious shortage of the skilled workers. However Tepco is denying the risk to state they still have the sufficient stock of the workers in other nuclear plants.

On the other hand, local media point out the lack of skilled workers is already starting to cause the recent troubles due to the continuous basic mis-operations.

Following up this article.. Tepco to re-interrogate 43 workers about 100 m3 overflow[URL]

On 3/7/2014, Tepco announced they hadn’t obtained any useful information from the interrogation.

The overflow of 100m3 contaminated water was caused by the wrong valve settings. However, nobody was supposed to work beside the issued valves that day, and also the valve settings were fixed when Tepco went to see the situation. It is possibly someone’s malicious act.

However Tepco still hasn’t found out who was involved and why regardless of their 2 weeks interrogation with over 100 workers. According to Tepco, “expert” is joining the investigation, but none of the details are announced. Some of the local media stated in Tepco’s press conference that this accident revealed Tepco’s vulnerability against “internal threat”. In this case, Tepco can be a victim.

Tepco still retains 3,600 tonnes of contaminated rainwater in underground reservoirs, which experienced the major leakage last Spring.

Tepco dug the ground, covered the hole with water shielding sheets, and called it the underground reservoir. In April of 2013, at least 3 of 7 reservoirs leaked the contaminated water.

They decided to abandon the reservoirs. However having the continuous typhoons causing overflow of the dams to surround tanks last Autumn, Tepco started reusing the faulty designed reservoirs in order to evacuate the rainwater that was mixed with contaminated water in the dams.

Tepco was supposed to send the newly added water back to the tanks, but they still cannot empty the reservoirs due to the shortage of other storage.

Currently 2 of 7 reservoirs retain the rainwater. One has 1,500 tonnes, the other one has 2,100 tonnes. At this moment, they still have no safer place to stock it.

Following up this article.. [100m3 overflow] Contaminated water is removed by “hand-digging” of human workers [URL]

The abnormality of tank water level trend was too slight to recognize, Tepco stated in the press conference of 3/5/2014.

When 100m3 of highly contaminated water overflowed from the tank, the operators were watching the monitor of tank water levels. However they didn’t notice the water overflowing.

In the report that Tepco submitted to NRA (Nuclear Regulation Authority) on 3/5/2014, it was simply because the water trend was represented in the scale of 0% ~ 100% on the monitor (See the picture below). Before the tank had the additional contaminated water, it was already 98% full. They therefore didn’t recognize 2% of the increase, which was shown as a “negligible gap” on the monitor.

The operators are employed by the different company from the monitor maker. It revealed the fact that Tepco is not supervising even the most basic things in Fukushima decommissioning process.

On 2/25/2014, Tepco damaged the power cable for reactor4 pool, which was installed by themselves.

It stopped one of the coolant systems of reactor4 pool, they ended up suspending fuel removal from the pool. They took about 4 hours to restart.

Tepco was drilling the ground in the south side of reactor4 in the process of improving the ground to stop groundwater flowing into the reactor buildings.

When they drilled approx. 1m in the ground, they damaged the power cable.

Regarding the cause, Tepco stated they were not informed of that the power cables were there by the outsourced company. Also, they had the “subjective impression” that any pipes or cables were not buried there.

Additionally, they actually found unexpected material when they started drilling, but they continued drilling without checking anything.

Following up this article.. Tepco to re-interrogate 43 workers about 100 m3 overflow[URL]

The overflowed tank had contaminated water up to 98% of its capacity before the overflowing accident, according to Tepco.

The primary cause of the overflow was because additional water was lead in due to the mis-operation, however there was the background that the tank was already nearly full since before. There is a risk that even other tanks can overflow in the potential earthquakes.

In the working group of 2/24/2014, NRA (Nuclear Regulation Authority) required Tepco to reduce the water level in the tanks to 95%.

However Tepco rejected their request “because of the shortage of contaminated water storage”.

Having contaminated water endlessly increasing, Tepco is having to use even the buffer capacity of the 3% (98% – 95%).